Reland of Pass SequencedTaskRunner to PowerSaveBlocker for ui/file ops

content/browser/DEPS

 include_rules = [
   # Allow inclusion of specific components that we depend on. We may only
   # depend on components which we share with the mojo html_viewer.
   "+components/filesystem",
   "+components/leveldb",
   "+components/link_header_util",
   "+components/mime_util",
   "+components/mus/public/interfaces",
   "+components/mus/public",
   "+components/network_session_configurator/switches.h",
@@ skipping 96 matching lines @@
   "+third_party/WebKit/public/platform/modules/bluetooth/web_bluetooth.mojom.h",
   "+third_party/WebKit/public/platform/modules/vr/vr_service.mojom.h"
 
   # DO NOT ADD ANY CHROME OR COMPONENTS INCLUDES HERE!!!
   # See https://sites.google.com/a/chromium.org/dev/developers/content-module
   # for more information.
 ]
 
 specific_include_rules = {
   # See https://crbug.com/612337.
-  "power_save_blocker.*\.(cc|h)": [
+  "(power_save_blocker_android\.cc"
+  "|power_save_blocker_android\.h"
+  "|power_save_blocker_chromeos\.cc"
+  "|power_save_blocker_impl\.cc"
+  "|power_save_blocker_impl\.h"
+  "|power_save_blocker_mac\.cc"
+  "|power_save_blocker_ozone\.cc"
+  "|power_save_blocker_win\.cc"
+  "|power_save_blocker_x11\.cc"
+  ")": [
     "-content",
 
     # These will move to //device/power_save_blocker.
     "+content/browser/power_save_blocker_impl.h",
     "+content/public/browser/power_save_blocker.h",
 
     # These dependencies need to be removed.
     "!content/browser/android/content_view_core_impl.h",
     "!content/browser/web_contents/web_contents_impl.h",
     "!content/public/browser/android/content_view_core.h",
-    "!content/public/browser/browser_thread.h",
     "!content/public/browser/web_contents_observer.h",
   ]
 }